Use a utility from MathExtras to clarify a check and avoid undefined behavior. Based...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141829 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index c3a0df3333c51765db7e3879231ad607ae6d80ee..d11bd94cb091a2ae5f74d752fd0dc7af931150d4 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -1679,7 +1679,7 @@ void SelectionDAGBuilder::visitBitTestHeader(BitTestBlock &B,
     UsePtrType = true;
   else {
     for (unsigned i = 0, e = B.Cases.size(); i != e; ++i)
-      if ((uint64_t)((int64_t)B.Cases[i].Mask >> VT.getSizeInBits()) + 1 >= 2) {
+      if (!isUIntN(VT.getSizeInBits(), B.Cases[i].Mask)) {
         // Switch table case range are encoded into series of masks.
         // Just use pointer type, it's guaranteed to fit.
         UsePtrType = true;